Searching for suitable expert witness to opine as to blood alcohol
level/range of defendant at time of accident when she crashed her vehicle
in remote location and was not discovered and rescued from vehicle
for another 12 hours. She had no access to alcoholic beverages while
trapped in vehicle. At hospital where she was treated for broken ribs
and hypothermia, the defendant tested at .082g/100 ml of blood.

I’m not sure if you already found someone, but I once used Dr. Nipper at Creighton University. He provided good evidence regarding retrograde extrapolation (figuring alcohol levels at a certain time based on specific known factors) . It’s great evidence, but you have know a lot of basic factors like last meal eaten, time of possible last drink, type of alcohol being consumed, body weight, etc.